ul {
  height: 340px;
  width: 340px;
  position: absolute;
  background-color: #ddd;
}
ul li {
  width: 100px;
  height: 100px;
  position: absolute;
  background-color: #87ceea;
  display: flex;
  font-size: 14px;
  color: #ffffff;
  font-weight: 700;
  align-items: center;
  justify-content: center;
}
ul li.active {
  background-color: #666666;
}
ul li:nth-of-type(1) {
  top: 10px;
  left: 10px;
}
ul li:nth-of-type(2) {
  top: 10px;
  left: 120px;
}
ul li:nth-of-type(3) {
  top: 10px;
  left: 230px;
}
ul li:nth-of-type(4) {
  top: 120px;
  left: 230px;
}
ul li:nth-of-type(5) {
  top: 230px;
  left: 230px;
}
ul li:nth-of-type(6) {
  top: 230px;
  left: 120px;
}
ul li:nth-of-type(7) {
  top: 230px;
  left: 10px;
}
ul li:nth-of-type(8) {
  top: 120px;
  left: 10px;
}
ul li:nth-of-type(9) {
  top: 120px;
  left: 120px;
}
